21163863912 has 64 divisors (see below), whose sum is σ = 53688622080. Its totient is φ = 6950956032.

The previous prime is 21163863893. The next prime is 21163863913. The reversal of 21163863912 is 21936836112.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21163863913) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1898868 + ... + 1909980.

It is an arithmetic number, because the mean of its divisors is an integer number (838884720).

Almost surely, 2^21163863912 is an apocalyptic number.

It is an amenable number.

21163863912 is an abundant number, since it is smaller than the sum of its proper divisors (32524758168).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21163863912 is a wasteful number, since it uses less digits than its factorization.

21163863912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12282 (or 12278 counting only the distinct ones).

The product of its digits is 93312, while the sum is 42.

The spelling of 21163863912 in words is "twenty-one billion, one hundred sixty-three million, eight hundred sixty-three thousand, nine hundred twelve".